This is a request for an ADAMHA Research Scientist Award (RSA). The proposed program of research extends current RSDA work, primarily On vicarious emotional responding (empathy-related reactions), which resulted in a heuristic model of the role of individual differences in emotional intensity and regulation in socioemotional functioning. Recently theorists in developmental, clinical, and social psychology have hypothesized regarding the role of individual differences in both emotionality (frequency and intensity of emotion) and regulation in social and emotional functioning. Based on theory and gaps in the current empirical literature, the purposes of the proposed research are to examine the additive and interactive contributions of individual differences in regulation (including coping behaviors and styles) and emotional reactivity (positive, negative, and general reactivity) to children's socioemotional functioning and behavior. Aspects of functioning and behavior of focal interest include: (a) the occurrence, intensity, and/or duration of directly induced emotions (e.g., anger, distress, and sadness); (b) occurrence and intensity of vicariously induced emotion to others in distress or need (sympathy and personal distress); (c) clarity of expression of negative and positive emotions and the tendency to monitor one s own expression of emotion and behavior; (d) socially appropriate behavior and peer acceptance; and (e) problem behaviors and shyness, including adults' perceptions of problem behaviors and shyness/inhibition among normal children and children at risk for internalizing and externalizing problems. A secondary goal is to obtain data on the relations of children's emotionality, regulation, and social functioning to the expression of emotion in the family, parents' discussions of emotion, and parents' reactions to children's expression of emotion. A multimethod approach will be used, involving self-report and behavioral measures, facial and physiological markers of emotion, and naturalistic as well as laboratory studies. Six studies are proposed. Several studies are two- or three-year follow- ups of two separate longitudinal samples. In these studies, individual differences in emotionality and various aspects of regulation will be used a predictors of several of the aforementioned aspects of socioemotional functioning. Emotionality and regulation are assessed with teacher and parent reports, child reports, behavioral measures, and/or physiological measures Prediction within and across time will be examined. In a related study, similar issues will be examined with a sample that includes children with moderate levels of internalizing and externalizing symptoms. In two additional studies, dispositional and socialization correlates of children's expressions of overt emotion with peer and the quality and success of children's coping behavior will be examined using naturalistic methods.